Biosensors based on laccase for detection of commercially reactive dyes

The results obtained using Trametes versicolor laccase modified graphite electrodes for detection of eleven different commercially reactive dyes are presented for the first time herein. The increase in current upon injection of the analyzed substrate was shown to be approximated by Michaelis–Menten type dependence. The calculated kinetic constants were used to evaluate the applicability of the laccase modified graphite electrode for the detection of reactive dyes in textile effluents.This paper was submitted as part of a Special Memorial Issue honoring George-Emil Baiulescu. This paper is part of the project CEEX 77/2006 "Computerized filtration and separation systems activated by ultrasounds and controlled by biosensors for textile processes-FILTSOFTUS'' and was supported by "Romanian Authority for Scientific Research/MATNANTECH''

MALDI-TOF mass spectrometry in textile industry

In this paper are presented the possibilities of using matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry in textile industry. MALDI-TOF mass spectrometry it is a convenient, versatile method for characterization and identification of dyes and pigments, and also for characterization of fibers and contaminants of the fabrics.(undefined

Non-destructive soluble solids content determination for ‘Rocha’ Pear Based on VIS-SWNIR spectroscopy under ‘Real World’ sorting facility conditions

In this paper we report a method to determine the soluble solids content (SSC) of 'Rocha' pear (Pyrus communis L. cv. Rocha) based on their short-wave NIR reflectance spectra (500-1100 nm) measured in conditions similar to those found in packinghouse fruit sorting facilities. We obtained 3300 reflectance spectra from pears acquired from different lots, producers and with diverse storage times and ripening stages. The macroscopic properties of the pears, such as size, temperature and SSC were measured under controlled laboratory conditions. For the spectral analysis, we implemented a computational pipeline that incorporates multiple pre-processing techniques including a feature selection procedure, various multivariate regression models and three different validation strategies. This benchmark allowed us to find the best model/preproccesing procedure for SSC prediction from our data. From the several calibration models tested, we have found that Support Vector Machines provides the best predictions metrics with an RMSEP of around 0.82 ∘ Brix and 1.09 ∘ Brix for internal and external validation strategies respectively. The latter validation was implemented to assess the prediction accuracy of this calibration method under more 'real world-like' conditions. We also show that incorporating information about the fruit temperature and size to the calibration models improves SSC predictability. Our results indicate that the methodology presented here could be implemented in existing packinghouse facilities for single fruit SSC characterization.Funding Agency CEOT strategic project UID/Multi/00631/2019 project OtiCalFrut ALG-01-0247-FEDER-033652 Ideias em Caixa 2010, CAIXA GERAL DE DEPOSITOS Fundacao para a Ciencia e a Tecnologia (Ciencia)info:eu-repo/semantics/publishedVersio

Laccase kinetics of degradation and coupling reactions

The ability of Trametes villosa laccase to degrade an azo dye (methyl orange) and to catalyze the coupling reactions between the aromatic amines and catechol was studied. It was found that the apparent Michaelis–Menten constants obtained from amperometric measurements were comparable to the ones obtained in the oxygen consumption experiments (8.20 and 7.40 µM, respectively). From the measurements of the mediated and mediatorless currents of azo dye degradation and coupling reactions itwas concluded that the addition of 1-hydroxybenzotriazole (HBT) as mediator considerably improves the catalytic efficiencies. It can be concluded that the mediated coupling of the aromatic amine with catechol opens the perspectives of physical removal of these polluting chemicals from the nature and the usage of the laccase immobilized onto macro-electrodes in online systems with continuous monitoring of the enzyme activity

Laccase polymerization of amino-phenol compounds

Abstracts of Papers of the American Chemical Society, 229, POLY331, U955-U955, 2005

Diffuse sclerosing variant of papillary thyroid carcinoma: outcomes of 33 cases

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Staining of wool using the reaction products of ABTS oxidation by Laccase : synergetic effects of ultrasound and cyclic voltammetry

The effects of ultrasound on 2,2′-Azinobis(3-ethylbenzothiazoline-6-sulfonate) enzymatic oxidation by laccase (Trametes villosa) has been studied by means of cyclic voltammetry. The reaction was allowed to proceed in the presence of a piece of wool and the coloration depth of the wool fabric was measured by means of K/S. It was observed that cyclic voltammetry is influenced the dyeing process and higher K/S values were obtained when the cyclic voltammetry was combined with the ultrasonic irradiation. Moreover, the K/S value is the sum of the values obtained when the wool staining is done in just the presence of cyclic voltammetry or in just the presence of ultrasound. The results obtained on the indigo carmine decolourization gives information on the importance of controlling the amount of ABTS+ formed during the ultrasonication process

Acetylations role in tau structure, electrostatics and interactions: molecular dynamics studies

Tau is a microtubule associated protein which stabilizes and promotes the assembly of microtubules in neurons.1 In its functional form it presents minor modifications, such as phosphorylation, but a large variety of post-translational modifications are also possible.2 Tau post-translational modifications are directly related with tau mal-functioning, aggregation and subsequent tauopathies. Investigation on tau hyperphosphorylation has dominated in the past years, since its known role in Alzheimers disease onset and progression. However, acetylation has gained attention, as this process is also responsible for tau pathological aggregation.3-4 Acetylation is a modification that occurs in lysine amino acids, adding an acyl group to the side chain NH moiety.5 This process changes the charge of this residue, making it neutral and consequently modifying the electrostatics of the whole protein. The presence of charged groups and electrostatic interactions are the major contributors for a final protein fold. The absence of these charges, via acetylation, will contribute to significant changes in taus structure and interactions. Molecular Dynamics (MD) simulations take advantage of precise simulation algorithms and present themselves as a robust way to understand biomolecules behavior, conformational preferences and interactions, even for intrinsically disordered proteins such as tau. Through this technique we are following the acetylation impact on the tau structure and its way of binding to the microtubule. In addition, it is intended to unveil the relationship between acetylation and aggregation, which results in tau associated diseases. In the past year, Castro and co-workers shed light on tau properties by predicting its 3D structure and disclosing the interaction pattern with microtubules and the ions from the intracellular fluid1. The present work took this input information to generate acetylated analogs and follow the impact of this modification on taus dynamic behavior.info:eu-repo/semantics/publishedVersio

Release of fragrances from cotton functionalized with carbohydrate-binding module proteins

Perspiration as a response to daily activity and physical exercise results in unpleasant odors that cause social unrest and embarrassment. To tackle it, functional textiles incorporating fragrances could be an effective clothing deodorizing product. This work presents two strategies for the release of -citronellol from functionalized cotton with carbohydrate-binding module (CBM)-based complexes (OBP::GQ20::CBM/-citronellolapproach 1 and CBM::GQ20::SP-DS3-liposome/-citronellolapproach 2). CBM from Cellulomonas fimi was fused with the odorant-binding protein (OBP::GQ20::CBM) and with an anchor peptide with affinity to the liposome membrane (CBM::GQ20::SP-DS3). In approach 1, OBP fusion protein served as a fragrance container, whereas in approach 2, the fragrance was loaded into liposomes with a higher cargo capacity. The two strategies showed a differentiated -citronellol release profile triggered by an acidic sweat solution. OBP::GQ20::CBM complex revealed a fast release (31.9% and 25.8% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively), while the CBM::GQ20::SP-DS3-liposome complex demonstrated a slower and controlled release (5.9% and 10.5% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively). Both strategies revealed high potential for textile functionalization aimed at controlled release of fragrances. The OBP::GQ20::CBM/-citronellol complex is ideal for applications requiring fast release of a high amount of fragrance, whereas the CBM::GQ20::SP-DS3-liposome/-citronellol complex is more suitable for prolonged and controlled release of a lower amount of -citronellol.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. F.G. and C.S. thanks FCT for their funding (SFRH/BD/114684/2016; SFRH/IF/00186/2015).info:eu-repo/semantics/publishedVersio

Kinetics of direct and substrate-mediated electron transfer of versatile peroxidase-modified graphite electrodes

Electron transfer (ET) of versatile peroxidase (VP) was studied in the bioelectrocatalytic reduction reaction of H2O2 at peroxidase- modified graphite electrodes to obtain additional information on the kinetic characteristics of this novel ligninolytic peroxidase. Rotating disk electrodes (RDE) experiments were performed at 0 V (vs. SCE) in two different buffers (tartrate buffer, pH 5.0; and citrate buffer, pH 3.0). From measurements of the mediated and mediatorless currents of H2O2 reduction at the RDE, the percentage of VP molecules involved in direct ET (≈55%) was calculated. The peroxidase-modified electrodes were used for determination of the donor substrates in RDE mode, and the results were interpreted in terms of catalytic efficiencies